Speaker
Phani Domalapally
(Centrum výzkumu Řež s.r.o.)
Description
The heat loads on the First Wall (FW) of the European DEMO are not yet defined, but when extrapolated from ITER, the loads can be quite high. As the DEMO will use Eurofer 97 as the structural material and Pressurized Water Reactor (PWR) conditions at the inlet, i.e. 15.5 MPa and 285 °C, the design of the heat sink gets complicated as the thermal conductivity of the heat sink material is quite low as well as the operating window of temperature (between 285 °C and 550 °C). As in ITER, there are two different kinds of heat sinks that have to be designed for the FW: the first one is normal heat flux channel and the second one is enhanced heat flux channel. For handling normal heat fluxes round tubes with counter current flow are chosen while for handling enhanced heat fluxes channel with the Hypervapotron configuration is chosen. Simulations were carried out to find out the limits from the thermal-hydraulic point of view using commercial Computational fluid dynamics code STAR-CCM+. For normal heat flux channels after optimization, the heat flux limit was found to be around 1.7 MW/m22 before reaching limits from the temperature point of view (550 °C for Eurofer). And for enhanced heat flux channels the same code is used where the boiling model used was previously validated with different Hypervapotron configurations. It was found that after optimization the heat sink cannot handle heat fluxes greater than 3 MW/m22 from thermal-hydraulic point of view before reaching the temperature limits of operation. Based on the results the operating limits of the different heat sinks at PWR conditions and Eurofer material as heat sink is assessed.
This work was carried out within the EUROfusion Breeding Blanket Project.
Co-authors
Mattia Dellabiancia
(Centrum výzkumu Řež s.r.o., Husinec-Řež, Czech Republic)
Phani Domalapally
(Centrum výzkumu Řež s.r.o., Husinec-Řež, Czech Republic)